A powder of melted particles, more than 95% by number of the particles exhibiting a circularity of greater than or equal to 0.85. The powder including more than 99.8% of a rare earth metal oxide and/or of hafnium oxide and/or of an aluminum oxide, as percentage by mass based on the oxides. The powder has a median particle size D.sub.50 of less than 15 μm, a 90 percentile of the particle sizes, D.sub.90, of less than 30 μm, and a size dispersion index (D.sub.90−D.sub.10)/D.sub.10 of less than 2, and a relative density of greater than 90%. The D.sub.n percentiles of the powder are the particle sizes corresponding to the percentages, by number, of n %, on the cumulative distribution curve of the size of the particles in the powder and the particle sizes are classified by increasing order.

A powder of melted particles, more than 95% by number of the particles exhibiting a circularity of greater than or equal to 0.85. The powder including more than 99.8% of a rare earth metal oxide and/or of hafnium oxide and/or of an aluminum oxide, as percentage by mass based on the oxides. The powder has a median particle size D.sub.50 of less than 15 μm, a 90 percentile of the particle sizes, D.sub.90, of less than 30 μm, and a size dispersion index (D.sub.90−D.sub.10)/D.sub.10 of less than 2, and a relative density of greater than 90%. The D.sub.n percentiles of the powder are the particle sizes corresponding to the percentages, by number, of n %, on the cumulative distribution curve of the size of the particles in the powder and the particle sizes are classified by increasing order.

The invention includes apparatus and methods for instantiating rare earth metals in a nanoporous carbon powder.

A refrigerator is provided, including rare earth cold accumulating material particles filled in a cold accumulating vessel. The rare earth cold accumulating material particles are a rare earth oxide or a rare earth oxysulfide. The rare earth cold accumulating material particles define a sintered body. An average crystal grain size of the sintered body is 0.5 to 5 μm, a porosity of the sintered body is 10 to 50 vol. %, and an average pore size of the sintered body is 0.3 to 3 μm. In an arbitrary cross-section of the rare earth cold accumulating material particles, a number of pores per a unit area of 10 μm×10 μm is 20 to 70.

A refrigerator is provided, including rare earth cold accumulating material particles filled in a cold accumulating vessel. The rare earth cold accumulating material particles are a rare earth oxide or a rare earth oxysulfide. The rare earth cold accumulating material particles define a sintered body. An average crystal grain size of the sintered body is 0.5 to 5 μm, a porosity of the sintered body is 10 to 50 vol. %, and an average pore size of the sintered body is 0.3 to 3 μm. In an arbitrary cross-section of the rare earth cold accumulating material particles, a number of pores per a unit area of 10 μm×10 μm is 20 to 70.

The invention relates to a system and a method for the processing of minerals containing the lanthanide series and the production of rare earth oxides, which allow a completely closed and continuous treatment of the different materials and desorbent agents involved in the process, thus improving the efficiency in the extraction and avoiding environmental risks associated. The method comprising the steps of: reception and conditioning of the raw material; desorption of valuable product through a plurality of mixing and reaction stages in which the raw material is contacted in countercurrent with a stream of desorbent solution; separation of fine solids; precipitation of secondary minerals through the use of a first reactive solution; precipitation of rare earth carbonates through the use of a second reactive solution; and drying and roasting of the rare earth carbonates to obtain rare earth oxides; wherein the method further comprises a secondary process that allows further processing of the residual mineral, and a dewatering and washing step wherein the residual mineral from the desorption step is washed and a lanthanide-containing liquid is recovered.

The invention relates to a system and a method for the processing of minerals containing the lanthanide series and the production of rare earth oxides, which allow a completely closed and continuous treatment of the different materials and desorbent agents involved in the process, thus improving the efficiency in the extraction and avoiding environmental risks associated. The method comprising the steps of: reception and conditioning of the raw material; desorption of valuable product through a plurality of mixing and reaction stages in which the raw material is contacted in countercurrent with a stream of desorbent solution; separation of fine solids; precipitation of secondary minerals through the use of a first reactive solution; precipitation of rare earth carbonates through the use of a second reactive solution; and drying and roasting of the rare earth carbonates to obtain rare earth oxides; wherein the method further comprises a secondary process that allows further processing of the residual mineral, and a dewatering and washing step wherein the residual mineral from the desorption step is washed and a lanthanide-containing liquid is recovered.

Provided herein are methods recovering rare earth elements (REEs) from a solution containing one or more REEs. These methods can comprise contacting an aqueous solution comprising one or more rare earth elements (REEs) with a solid sequestration media (e.g., a stabilized flue gas desulfurization (sFGD) material, or a sludge by-product from a water treatment process) to provide a REE-containing solid feedstock; and contacting the solid feedstock with an extraction solution to generate a rare earth element (REE) solution.

Provided herein are methods recovering rare earth elements (REEs) from a solution containing one or more REEs. These methods can comprise contacting an aqueous solution comprising one or more rare earth elements (REEs) with a solid sequestration media (e.g., a stabilized flue gas desulfurization (sFGD) material, or a sludge by-product from a water treatment process) to provide a REE-containing solid feedstock; and contacting the solid feedstock with an extraction solution to generate a rare earth element (REE) solution.

The present invention relates to silicon coated metal microparticles in which at least a part of a surface of a metal microparticle composed of at least one of metal elements or metalloid elements is coated with silicon, wherein the silicon coated metal microparticles are a product obtained by a reduction treatment of silicon compound coated precursor microparticles in which at least a part of a surface of a precursor microparticle containing a precursor of the metal microparticles is coated with a silicon compound, or silicon doped precursor microparticles containing a precursor of the metal microparticles. Because it is possible particularly to strictly control a particle diameter of the silicon compound coated metal microparticle by controlling conditions of the reduction treatment, design of a more appropriate composition can become facilitated, compared with a conventional composition, in terms of diversified usages and desired properties of silicon compound coated metal microparticles.